Instrumental methods of approximating functions of random arguments and of determining their moments using spectrum analyzers (Q1901551)

It is known that many problems of science and practice lead to a construction of mathematical models of physical systems with an input and an output. Moreover, random elements very often appear in such models. An aim of the paper is to present such a mathematical model in the form of a functional relation between the output characteristics and some input quantities. The Chebyshev polynomials and the Fourier series are employed to determine an approximation of the above mentioned functional relations and of their first and second moments. The corresponding Fourier coefficients are determined instrumentally using a spectrum analyzer. The paper is written in an understandable way.